Although Wales had been a relative backwater during the First Civil War, it was a major focus of activity during the second conflict, and events in Wales catalysed the military phase of the War. The first shots of the Second Civil War came from Colonels Poyer and Laugharne who declared for the King on 23rd March. Poyer and Laugharne had commanded Parliamentary forces in Wales during the First Civil War but had become increasingly alarmed by rising Parliamentary radicalism, and had entered into secret correspondence with Royalists in 1647.
When Parliament attempted to disband troops under their command without paying them, this resentment turned into open mutiny, and they quickly swept east from their Pembrokeshire stronghold with 8000 men under their command, threatening to take Cardiff. Although the Parliamentary forces were heavily outnumbered, they inflicted a stinging defeat on the Royalist rebels at St. Fagans on 8th May. After this reverse, Poyer and Laugharne retreated to Pembroke Castle and were finally starved into submission on 11th July. The Welsh part of the insurrection was over.
The frustration and resentment experienced by the Welsh ex-Parliamentarians was mimicked by other groups across the country who merged with Royalist sympathisers in a revolt which was more anti-Parliament and Army than pro-King. Five years of oppressive taxes and indiscriminate quartering had produced a truly popular uprising, and many communities had been hurt by economic recession and longed for the old familiar rhythms of the Church of England. By May 1648, Berwick and Carlisle were in Royalist hands and Surrey and Kent were also in open revolt.
With England and Wales in revolt, the Scottish Engagers marched across the border under the command of the King's old ally, the Duke of Hamilton. It would become quickly apparent that Hamilton was hopelessly out of his depth - especially up against Oliver Cromwell. Having invaded through Lancashire, and not the more Royalist Yorkshire, Hamilton rode into Preston and placed his ill-trained, half-starved troops up against the might of the fast-approaching New Model Army. On the morning of 17th August 1648, Hamilton's troops positioned themselves north of Preston on the edge of Ribbleton Moor. There they waited, in the hedges and sunken lanes, for Cromwell's arrival. When the New Model Army marched in they were met with a sea of pikes.
Cromwell's cavalry found the ground too soft and it became a battle of hand to hand infantry combat. But by evening, the Engagers were fast retreating across Preston Bridge in an attempt to put the Ribble between them.
The retreat turned into a rout as Cromwell unleashed his awesome cavalry onto the hapless Scottish infantry. They were forced back to the river, many jumping in and swimming across with their horses. The unlucky Scots left fighting on the bank were cut down in their hundreds. As the rain began to pour, Cromwell turned his fire on the troops defending the bridges. The brave brigades fought to the death in the face of Cromwell's overwhelming might. Over 1,000 Scots were killed at Preston. To finish off any remaining opposition, Cromwell pursued them down to Wigan. The clean-up operation captured Hamilton. His next stop was the block.
While Cromwell was busy dispersing the Scots, Fairfax was showing a similar lack of mercy in Colchester. After a long siege, Colchester gave in and surrendered to Fairfax's surrounding forces. Hoping for clemency, they were proved horribly wrong. The town was stormed, residents butchered and enemy officers executed by firing squad. Cromwell, Fairfax and the whole Army were in no mood for messing around anymore. The chivalry of the First Civil War was gone; the elegant games of Rupert and Manchester were a thing of the past. In its place, a new brutality and an urgent desire to end this interminable conflict once and for all.
Returning to war for the second time was the worst thing Charles could have done. It sealed his fate. Charles was now seen not only as an irresponsible King who had no regard for the well-being of his people, he also came to be seen as defying the judgement of God. For that, only one penalty was appropriate - death.